So, I've been working on a project to connect my quadcopter's ardupilot with a raspberry pi via MAVlink. The ardupilot is a great little controller with extensive autopilot features already programmed in but I'd like to use a raspberry pi to be able to gather sensor data as well as receive GPS waypoints over GSM and feed it back to the ardupilot. My plan is to be able to use a near-infrared camera to image forests in order to monitor vegetation health. I'm also super tempted to see if I can interface the pi with a low cost thermal camera.
So far I've been able to successfully get my ardupilot to communicate with my raspberry pi and I'm researching different ways of connecting the Pi to cellular networks. I was wondering if anyone has any experience with using the Pi with GSM and can point me in the right direction. I do NOT intend to send sensor data or images over GSM. That seems like a quick way to wrack up an expensive phone bill. All images and other data will simply be saved to memory. What I would like to be able to do is to send GPS coordinates to the pi and receive periodic GPS updates.